Re: [PATCH v1] usb: dwc2: add pci_device_id driver_data parse support

[Greg Kroah-Hartman]

On Thu, May 18, 2023 at 05:22:40PM +0800, Yinbo Zhu wrote:
> The dwc2 driver has everything we need to run in PCI mode except
> for pci_device_id driver_data parse.  With that to set Loongson
> dwc2 element and added identified as PCI_VENDOR_ID_LOONGSON
> and PCI_DEVICE_ID_LOONGSON_DWC2 in dwc2_pci_ids, the Loongson
> dwc2 controller will work.
> 
> Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
> ---
>  drivers/usb/dwc2/core.h   |  1 +
>  drivers/usb/dwc2/params.c | 33 +++++++++++++++++++++++++++++++--
>  drivers/usb/dwc2/pci.c    | 14 +-------------
>  include/linux/pci_ids.h   |  2 ++
>  4 files changed, 35 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
> index 0bb4c0c845bf..c92a1da46a01 100644
> --- a/drivers/usb/dwc2/core.h
> +++ b/drivers/usb/dwc2/core.h
> @@ -1330,6 +1330,7 @@ irqreturn_t dwc2_handle_common_intr(int irq, void *dev);
>  /* The device ID match table */
>  extern const struct of_device_id dwc2_of_match_table[];
>  extern const struct acpi_device_id dwc2_acpi_match[];
> +extern const struct pci_device_id dwc2_pci_ids[];
>  
>  int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg);
>  int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg);
> diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
> index 21d16533bd2f..f7550d293c2d 100644
> --- a/drivers/usb/dwc2/params.c
> +++ b/drivers/usb/dwc2/params.c
> @@ -7,6 +7,8 @@
>  #include <linux/module.h>
>  #include <linux/of_device.h>
>  #include <linux/usb/of.h>
> +#include <linux/pci_ids.h>
> +#include <linux/pci.h>
>  
>  #include "core.h"
>  
> @@ -55,6 +57,14 @@ static void dwc2_set_jz4775_params(struct dwc2_hsotg *hsotg)
>  		!device_property_read_bool(hsotg->dev, "disable-over-current");
>  }
>  
> +static void dwc2_set_loongson_params(struct dwc2_hsotg *hsotg)
> +{
> +	struct dwc2_core_params *p = &hsotg->params;
> +
> +	p->phy_utmi_width = 8;
> +	p->power_down = DWC2_POWER_DOWN_PARAM_NONE;
> +}
> +
>  static void dwc2_set_x1600_params(struct dwc2_hsotg *hsotg)
>  {
>  	struct dwc2_core_params *p = &hsotg->params;
> @@ -281,6 +291,22 @@ const struct acpi_device_id dwc2_acpi_match[] = {
>  };
>  MODULE_DEVICE_TABLE(acpi, dwc2_acpi_match);
>  
> +const struct pci_device_id dwc2_pci_ids[] = {
> +	{
> +		PCI_DEVICE(PCI_VENDOR_ID_SYNOPSYS, PCI_PRODUCT_ID_HAPS_HSOTG),
> +	},
> +	{
> +		PCI_DEVICE(PCI_VENDOR_ID_STMICRO,
> +			   PCI_DEVICE_ID_STMICRO_USB_OTG),
> +	},
> +	{
> +		PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, PCI_DEVICE_ID_LOONGSON_DWC2),
> +		.driver_data = (unsigned long)dwc2_set_loongson_params,
> +	},
> +	{ /* end: all zeroes */ }
> +};
> +MODULE_DEVICE_TABLE(pci, dwc2_pci_ids);
> +
>  static void dwc2_set_param_otg_cap(struct dwc2_hsotg *hsotg)
>  {
>  	switch (hsotg->hw_params.op_mode) {
> @@ -929,10 +955,13 @@ int dwc2_init_params(struct dwc2_hsotg *hsotg)
>  		set_params(hsotg);
>  	} else {
>  		const struct acpi_device_id *amatch;
> +		const struct pci_device_id *pmatch;
>  
>  		amatch = acpi_match_device(dwc2_acpi_match, hsotg->dev);
> -		if (amatch && amatch->driver_data) {
> -			set_params = (set_params_cb)amatch->driver_data;
> +		pmatch = pci_match_id(dwc2_pci_ids, to_pci_dev(hsotg->dev->parent));

Ick, this means this is not a "real" PCI driver, right?  Why not?

Please tie into the PCI device probe call, don't walk all PCI devices
like this.

How are you _sure_ that the parent is really a PCI device?  That is very
very fragile and will break.

Do this properly instead.


> +
> +		if ((amatch && amatch->driver_data) || (pmatch && pmatch->driver_data)) {
> +			set_params = (set_params_cb)pmatch->driver_data;
>  			set_params(hsotg);
>  		}
>  	}
> diff --git a/drivers/usb/dwc2/pci.c b/drivers/usb/dwc2/pci.c
> index b7306ed8be4c..f3a1e4232a31 100644
> --- a/drivers/usb/dwc2/pci.c
> +++ b/drivers/usb/dwc2/pci.c
> @@ -24,7 +24,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/usb/usb_phy_generic.h>
>  
> -#define PCI_PRODUCT_ID_HAPS_HSOTG	0xabc0
> +#include "core.h"
>  
>  static const char dwc2_driver_name[] = "dwc2-pci";
>  
> @@ -122,18 +122,6 @@ static int dwc2_pci_probe(struct pci_dev *pci,
>  	return ret;
>  }
>  
> -static const struct pci_device_id dwc2_pci_ids[] = {
> -	{
> -		PCI_DEVICE(PCI_VENDOR_ID_SYNOPSYS, PCI_PRODUCT_ID_HAPS_HSOTG),
> -	},
> -	{
> -		PCI_DEVICE(PCI_VENDOR_ID_STMICRO,
> -			   PCI_DEVICE_ID_STMICRO_USB_OTG),
> -	},
> -	{ /* end: all zeroes */ }
> -};
> -MODULE_DEVICE_TABLE(pci, dwc2_pci_ids);
> -
>  static struct pci_driver dwc2_pci_driver = {
>  	.name = dwc2_driver_name,
>  	.id_table = dwc2_pci_ids,
> diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
> index e43ab203054a..6481f648695a 100644
> --- a/include/linux/pci_ids.h
> +++ b/include/linux/pci_ids.h
> @@ -157,6 +157,7 @@
>  #define PCI_VENDOR_ID_PCI_SIG		0x0001
>  
>  #define PCI_VENDOR_ID_LOONGSON		0x0014
> +#define PCI_DEVICE_ID_LOONGSON_DWC2	0x7a04
>  
>  #define PCI_VENDOR_ID_SOLIDIGM		0x025e
>  
> @@ -2356,6 +2357,7 @@
>  #define PCI_DEVICE_ID_SYNOPSYS_HAPSUSB3_AXI	0xabce
>  #define PCI_DEVICE_ID_SYNOPSYS_HAPSUSB31	0xabcf
>  #define PCI_DEVICE_ID_SYNOPSYS_EDDA	0xedda
> +#define PCI_PRODUCT_ID_HAPS_HSOTG       0xabc0

Please read the top of this file for why you should not add new ids
here.

thanks,

greg k-h